from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The branch of geology that deals with the origin, composition, structure, and alteration of rocks.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. the study of the origin, composition and structure of rock
from the GNU version of the Collaborative International Dictionary of English
- n. The department of science which is concerned with the mineralogical and chemical composition of rocks, and with their classification: lithology.
- n. A treatise on petrology.
from The Century Dictionary and Cyclopedia
- n. The study of rocks from the point of view of their mineralogical composition; lithology; petrography. By some this term is used in a more limited sense. See the quotation, and also petrography.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. the branch of geology that studies rocks: their origin and formation and mineral composition and classification
From petro- + -logy. (Wiktionary)